Display calibration methods with user settings feeback

ABSTRACT

Reference image data from a reference display is utilized to manually and/or automatically calibrate a display. The reference image data is compared to measured image data from the display to derive display control settings and feedback for users and/or to automatically adjust the display. In one instance, a graphical user interface is used to relay feedback information as a user manually adjusts a display. The feedback can include suggestions for adjusting existing controls (e.g., brightness, contrast, etc.) so that a user does not have to directly interpret gamut and/or gamma information. In other instances, the feedback information is utilized to automatically adjust the display without user involvement.

TECHNICAL FIELD

The subject matter relates generally to displays, and more particularlyto systems and methods for adjusting display parameters.

BACKGROUND

The representation of video and other images often differs from theoriginating source. Many factors can contribute to this, but most of thealteration is due to the characteristics of the display device itself.Thus, a reference display that is utilized to edit and create sourcematerial can display colors and intensities much differently than an enduser's display. For example, most displays have settings such asbrightness, contrast, hue, and backlight. The levels of those settingsare either predefined by manufacturers of the displays (e.g., displaymodes are set as dynamic, standard, cinema, game, etc.) or manipulatedby users of the displays. However, none of these methods provide thesettings which will closely match the displays to the reference displays(e.g., Rec.709 displays) on which all the critical color correction andgrading has been done by, for example, directors and colorists duringthe post production of the image contents. It is very difficult forusers to find correct settings of their displays without any feedback ofwhat has been changed as settings of the displays are changed.

SUMMARY

Comparisons of reference image data and measured image data areleveraged to provide display parameter feedback. This allows a user'sdisplay to be manually and/or automatically corrected to a referencedisplay. The reference display is generally utilized for editing andcreating an original image content source that a user desires to view.Thus, a user can view the content as it was originally designed to beviewed, despite the user having a different model and/or type ofdisplay. In one instance, a graphical user interface is used to relayfeedback information as a user manually adjusts a display. The feedbackcan include suggestions for adjusting existing controls (e.g.,brightness, contrast, etc.) so that a user does not have to directlyinterpret gamut and/or gamma information and the like. In anotherinstance, the feedback information is utilized to automatically adjustthe display without user involvement.

The above presents a simplified summary of the subject matter in orderto provide a basic understanding of some aspects of subject matterembodiments. This summary is not an extensive overview of the subjectmatter. It is not intended to identify key/critical elements of theembodiments or to delineate the scope of the subject matter. Its solepurpose is to present some concepts of the subject matter in asimplified form as a prelude to the more detailed description that ispresented later.

To the accomplishment of the foregoing and related ends, certainillustrative aspects of embodiments are described herein in connectionwith the following description and the annexed drawings. These aspectsare indicative, however, of but a few of the various ways in which theprinciples of the subject matter can be employed, and the subject matteris intended to include all such aspects and their equivalents. Otheradvantages and novel features of the subject matter can become apparentfrom the following detailed description when considered in conjunctionwith the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a display correction system in accordancewith an aspect of an embodiment.

FIG. 2 is another block diagram of a display correction system inaccordance with an aspect of an embodiment.

FIG. 3 is an illustration of a display calibration system with agraphical user feedback interface in accordance with an aspect of anembodiment.

FIG. 4 is an illustration of gamut color on a graphical user feedbackinterface in accordance with an aspect of an embodiment.

FIG. 5 is an illustration of gamma on a graphical user feedbackinterface in accordance with an aspect of an embodiment.

FIG. 6 is an illustration of an example of display control settings inaccordance with an aspect of an embodiment.

FIG. 7 is a flow diagram of a method of adjusting display parameters inaccordance with an aspect of an embodiment.

FIG. 8 is another flow diagram of a method of adjusting displayparameters in accordance with an aspect of an embodiment.

DETAILED DESCRIPTION

The subject matter is now described with reference to the drawings,wherein like reference numerals are used to refer to like elementsthroughout. In the following description, for purposes of explanation,numerous specific details are set forth in order to provide a thoroughunderstanding of the subject matter. It can be evident, however, thatsubject matter embodiments can be practiced without these specificdetails. In other instances, well-known structures and devices are shownin block diagram form in order to facilitate describing the embodiments.

As used in this application, the term “component” is intended to referto hardware, software, or a combination of hardware and software inexecution. For example, a component can be, but is not limited to being,a process running on a processor, a processor, an object, an executable,and/or a microchip and the like. By way of illustration, both anapplication running on a processor and the processor can be a component.One or more components can reside within a process and a component canbe localized on one system and/or distributed between two or moresystems. Functions of the various components shown in the figures can beprovided through the use of dedicated hardware as well as hardwarecapable of executing software in association with appropriate software.

When provided by a processor, the functions can be provided by a singlededicated processor, by a single shared processor, or by a plurality ofindividual processors, some of which can be shared. Moreover, explicituse of the term “processor” or “controller” should not be construed torefer exclusively to hardware capable of executing software, and canimplicitly include, without limitation, digital signal processor (“DSP”)hardware, read-only memory (“ROM”) for storing software, random accessmemory (“RAM”), and non-volatile storage. Moreover, all statementsherein reciting instances and embodiments of the invention are intendedto encompass both structural and functional equivalents. Additionally,it is intended that such equivalents include both currently knownequivalents as well as equivalents developed in the future (i.e., anyelements developed that perform the same function, regardless ofstructure).

Typically when a creator of content such as video, for example,finalizes their creation, they pay particular attention to the “look”and “feel” of the content. Color hues, intensity levels, and othervisual information play an important part in accurately portraying theart to a viewer. However, much of this information can be lost due toalteration of this information by a viewing device such as a display ormonitor. The techniques described herein allow a display device to bemanually and/or automatically corrected. Suggestions or feedback canalso be supplied to a user to allow for adjustments to the controlsettings of a display without a user being knowledgeable about how theadjustments directly affect gamma or gamut and the like.

FIG. 1 shows a block diagram of a display correction system 100 thatutilizes a display correction component 102 to determine display settingcorrections from measured image data 104 and reference image data 108for display device 106. The display correction system 100 can beutilized with any type of display device such as for example, computermonitors, televisions, film screens, and/or photo display devices andthe like. The reference image data 108 can include data such as, forexample, gamma and gamut information from a reference display that canbe utilized, for example, for post production of films and other imagesand the like. The measured image data 104 is data that is typicallydirectly measured from a display device such as an end user's displayand the like. For example, image data can be obtained by measuring areasor “patches” on a display using a specialized device called aspectroradiometer which measures the spectral power distributions ofilluminants. Thus, for example, gamma characteristics can be obtainedvia a series of patches that are measured directly from a display. Afterthe measurement, a gamma curve can be drawn in a plot, “luminance vs.digital value.” This gamma can be used to compensate a mismatch with areference gamma.

In this instance, the display correction component 102 can provide thedetermined display setting corrections to manually and/or automaticallyadjust the display device 106. Thus, a user is not required to be in afeedback loop between the display device 106 and the display correctioncomponent 102 in order to calibrate the display device 106 with regardto reference image data 108. Some displays allow control of the displaysettings via external means, such as via a display cable and/or wirelessconnections and the like.

In FIG. 2, a display correction system 200 employs a display correctioncomponent 202 that receives measured image data 204 and reference imagedata 214 and interfaces with user 206 and/or display device 208. Thedisplay correction device 202 utilizes a comparator 210 to process themeasured image data 204 and compare it to the reference image data 214.The comparator 210 can determine to what degree the measured image data204 and the reference image data 214 disagree. In one instance, when aratio of the compared data is less than a value of 1.0, the data can beconstrued to be substantially the same from a visual perspective. Thistype of threshold can be used to indicated when a display is correctlycalibrated to the reference image data 214. The comparator 210 can alsogenerate graphical comparisons of the data and present it to a user 206.Examples of graphical user interfaces are provided infra (see e.g.,FIGS. 4 and 5).

The display correction component 202 can also utilize a settingscomponent 212 that uses the compared data from the comparator 210 todetermine control settings for proper display corrections. The settingscomponent 212, for example, can interpret the compared data and derivesetting corrections for brightness, contrast, hue, and/or backlight andthe like. The derived setting corrections help in correctly calibratingthe display device 208 to the reference image data 214. The suggestedcontrol settings are especially useful for inexperienced users becausethey provide feedback in an easily understood form. The user candirectly apply the suggestions to the control settings of their displaywithout having to interpret complicated gamut and/or gamma charts andthe like. Thus, in one instance, the settings component 212 can providefeedback to the user 206 who then can adjust the display device 208. Inanother instance, the settings component 212 can directly interact withthe display device 208 to automatically adjust its control settingsand/or gamut/gamma plots and the like.

Most consumer level displays (e.g., LCD, LCoS, Plasma, DLP, CRT) showvideos/pictures with different gamma and gamut color from referencedisplays (e.g., High quality CRTs used in color correction/grading inpost production facility). Manufacturers are making efforts to enhanceimage qualities in terms of colors, contrast, and gammas and often claimthat their displays show wider gamut colors, higher contrast ratios,etc. However, those colors, contrast, gammas are quite different fromthose seen in reference displays which are used to create contents inpost production. As a result, a director or colorist's intent is notfaithfully reproduced in those consumer level displays.

The systems and methods provided herein can provide a feedback system inorder to help a user find a correct setting of their display so that itis calibrated to a reference display as close as possible for morefaithful reproduction of reference colors, gamma, and contrast. In oneinstance, feedback can be given in the form of a graphical userinterface (GUI) on a computer screen. Instances provided herein canprovide a means to help to find more precise settings of displays(brightness, contrast, hue, backlight, etc.) with real-time feedbacks ofmeasurements of current settings. This can be accomplished in the formof a GUI on a computer for users to easily understand the difference oftheir displays from the reference displays and keep manipulating thosesettings until they see the smallest difference. Similarly, the feedbackcan be used to automatically manipulate the settings of a displaywithout user interaction

FIG. 3 shows an example 300 of a feedback system 302 comprising a PC(personal computer) 306, display 308, and a measurement sensor (e.g.,spectroradiometer) 304 that measures a patch 310. The measurement sensor304 is connected with the PC 306 via a standard communication channel(e.g., USB or RS-232C). The software running on the PC 306 can haveseveral graphical panels. Two examples are 402, 502 as shown in FIG. 4and FIG. 5, respectively. FIG. 4 shows an example 400 of the differencebetween measured gamut colors and reference gamut colors. FIG. 5 showsan example 500 of gamma from measured and from reference image data. Themeasurement can be done with a measurement sensor attached to a display.The sensor can measure selected color patches on a display screen. FIG.6 shows an example 600 of control settings 602 of a display to bemeasured (e.g., brightness, contrast, hue, backlight). These settings,typically initially set by manufacturers of displays, can be controlledby users on the display screen, and will affect the gamut, contrast, andgamma of the display.

Once the calibration procedure starts, users can see the controlsettings on their display screen. If they initiate the measurement onthe PC 306, a number of patches 310 can be shown on the display 308 andthe measurement sensor 304 can measure each patch. A display correctionsystem provided herein, for example, can reside on a PC and cancalculate gamut color, contrast, and gamma from the measurement and showthem with the reference data graphically on a display screen (see e.g.,FIGS. 4 and 5). The users can then see the difference between themeasured and the reference image data and can appropriately adjust thesettings on the display screen, initiating the next measurement.

The new measured data can be fed back to the display correction system,and calculated gamma, gamut, and contrast can then be shown on thedisplay screen for users to decide whether they should repeat theprocedure or stop when the proper settings are found for the display.During this procedure, to give an idea to users which settings theyshould control, the display correction system can suggest userrecommended settings for adjustment. For example, if the displaycorrection system sees a large difference in the gamut color, but asmall difference in the gamma, it can ask users to adjust hue settingonly. In the opposite case (e.g., large difference in the gamma, butsmall difference in the gamut color), it can ask users to adjustbrightness and contrast settings.

In view of the exemplary systems shown and described above,methodologies that can be implemented in accordance with the embodimentswill be better appreciated with reference to the flow charts of FIGS. 7and 8. While, for purposes of simplicity of explanation, themethodologies are shown and described as a series of blocks, it is to beunderstood and appreciated that the embodiments are not limited by theorder of the blocks, as some blocks can, in accordance with anembodiment, occur in different orders and/or concurrently with otherblocks from that shown and described herein. Moreover, not allillustrated blocks may be required to implement the methodologies inaccordance with the embodiments.

In FIG. 7, a flow diagram of a method 700 of adjusting displayparameters in accordance with an aspect of an embodiment is shown. Themethod 700 starts 702 by receiving reference image data for a referencedisplay device 704. The reference image data is typically derived fromreference displays utilized, for example, in post-production work andother content editing and/or creation work and the like. These referencedisplays generally duplicate the colorist's and/or director's trueintent for the content being viewed. In most cases, end users do notaccurately view this information because their display devices are notof similar quality and/or sophistication as the reference displays. Theend user's display can also be of a different type such as, for example,an LCD display device compared to a reference CRT display device. Thesedifferences typically impact the way the content is viewed.

Measured image data is then received for a display device 706. Themeasured data is typically obtained from the end user's display using asensor mounted to the display to accurately read color and intensityinformation. For example, various color patches can be displayed andread to obtain the measured image data. Measured image data andreference image data are then compared to determine display settingcorrections to allow manual and/or automatic adjustment of a displaydevice 708, ending the flow 710. The display setting corrections help tocompensate for the differences between the data sets. This informationcan be relayed to a user as feedback so that the user can makeadjustments manually on a display device and/or the information can beused to directly control the display device to automatically adjust itscontrol settings.

Looking at FIG. 8, another flow diagram of a method 800 of adjustingdisplay parameters in accordance with an aspect of an embodiment isillustrated. The method 800 starts 802 by comparing measured image dataand reference image data to determine setting corrections for a displaydevice 804. As discussed above, the reference image data can be obtainedfrom, for example, post production displays used to prepare versions ofcontent and the like. The measured image data is typically measured inreal-time from a display that needs to be calibrated based on thereference image data. The determined setting corrections are thenutilized to suggest display control settings adjustments 806, ending theflow 808.

Oftentimes, the end results of comparing reference and measured imagedata are graphical representations of gamut and/or gamma differences(e.g., see FIGS. 4 and 5). Inexperienced end users may not be able tocorrectly interpret which controls for their displays need to beadjusted to bring the graphical representations in line with each other.Thus, suggestions or feedback are derived from the determinedcorrections for individual display controls such as, for example, hue,brightness, contrast, and/or backlight and the like (see e.g., FIG. 6).This allows a user to calibrate their display without having tointerpret complicated graphs. The user can just follow the suggestionsand repeat the process until the feedback indicates the display isproperly calibrated (e.g., using a threshold ratio value <1.0, etc.)and/or the user is satisfied visually with the calibration process.

In one instance, a data packet, transmitted between two or more devicesthat facilitates display adjustment is comprised of, at least in part,information relating to a display parameter adjustment system thatutilizes, at least in part, image control setting feedback derived fromcomparing measured image data from a first display and image data from areference display.

It is to be appreciated that the systems and/or methods of theembodiments can be utilized in gamma correction facilitating computercomponents and non-computer related components alike. Further, thoseskilled in the art will recognize that the systems and/or methods of theembodiments are employable in a vast array of electronic relatedtechnologies, including, but not limited to, computers, video playbackdevices, set top boxes, displays and/or handheld electronic devices, andthe like.

What has been described above includes examples of the embodiments. Itis, of course, not possible to describe every conceivable combination ofcomponents or methodologies for purposes of describing the embodiments,but one of ordinary skill in the art can recognize that many furthercombinations and permutations of the embodiments are possible.Accordingly, the subject matter is intended to embrace all suchalterations, modifications and variations that fall within the spiritand scope of the appended claims. Furthermore, to the extent that theterm “includes” is used in either the detailed description or theclaims, such term is intended to be inclusive in a manner similar to theterm “comprising” as “comprising” is interpreted when employed as atransitional word in a claim.

1. A system, comprising: a comparator that determines differences inimage data representative of a first display and image data measuredfrom a second display; and a settings component that determines imagecontrol settings for the second display based on the compared data. 2.The system of claim 1, wherein the first display image data comprisingat least gamut and gamma data.
 3. The system of claim 1, wherein theimage control settings comprising at least one of brightness, contrast,hue and backlight.
 4. The system of claim 1, wherein the settingscomponent automatically adjusts the image control settings for thesecond display.
 5. The system of claim 4, wherein the settings componentadjusts the second display to achieve a color difference value of lessthan 1.0.
 6. The system of claim 1, wherein the settings componentrelays image control setting feedback based on the compared data to auser.
 7. A method, comprising: comparing image data representative of afirst display and image data measured from a second display; anddetermining image control settings for the second display based on thecompared data.
 8. The method of claim 7 further comprising: utilizingfirst display image data comprising at least gamut and gamma data. 9.The method of claim 7 further comprising: determining image controlsettings for at least one of brightness, contrast, hue and backlight.10. The method of claim 7 further comprising: automatically adjustingthe image control settings for the second display utilizing the measureddisplay data.
 11. The method of claim 7 further comprising: relayingimage control setting suggestions based on the compared data to a user.12. The method of claim 7 further comprising: utilizing the determinedimage control settings to adjust the second display to achieve a colordifference value of less than 1.0.
 13. A system, comprising: means forcomparing image data representative of a first display and image datameasured from a second display; and means for determining image controlsettings for the second display based on the compared data.
 14. Thesystem of claim 13 further comprising: means for automatically adjustingthe second display based on the compared data.
 15. The system of claim13 further comprising: means for suggesting image control settingchanges to a user based on the compared data.
 16. A data packet,transmitted between two or more devices, that facilitates displayadjustment, the data packet comprising, at least in part, informationrelating to a display parameter adjustment system that utilizes, atleast in part, image control setting feedback derived from comparingmeasured image data from a first display and image data from a referencedisplay.
 17. A computer readable medium having stored thereon computerexecutable components of the system of claim
 1. 18. A device employingthe method of claim 7 comprising at least one selected from the groupconsisting of a computer, a video playback device, a set top boxes, adisplay and/or a handheld electronic device.
 19. A device employing thesystem of claim 1 comprising at least one selected from the groupconsisting of a computer, a video playback device, a set top boxes, adisplay and/or a handheld electronic device.